From 24d5dfb5527d46da097b56b7cfc3b28ec8f8ad3e Mon Sep 17 00:00:00 2001
From: Marcus Schweda <marcus.schweda@posteo.de>
Date: Thu, 3 Nov 2016 15:25:04 +0100
Subject: [PATCH] Dynamic assembly checks to prevent NotSupprotedExceptions
 from System.Reflection.Emit Fixes #5487

---
 .../ApplicationParts/AssemblyPart.cs          |  7 +++++++
 .../Compilation/ViewsFeatureProvider.cs       |  2 +-
 .../ApplicationParts/AssemblyPartTest.cs      | 19 +++++++++++++++++
 .../Compilation/ViewsFeatureProviderTest.cs   | 21 +++++++++++++++++++
 4 files changed, 48 insertions(+), 1 deletion(-)

diff --git a/src/Microsoft.AspNetCore.Mvc.Core/ApplicationParts/AssemblyPart.cs b/src/Microsoft.AspNetCore.Mvc.Core/ApplicationParts/AssemblyPart.cs
index a091013710..f18da3a406 100644
--- a/src/Microsoft.AspNetCore.Mvc.Core/ApplicationParts/AssemblyPart.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Core/ApplicationParts/AssemblyPart.cs
@@ -47,6 +47,13 @@ namespace Microsoft.AspNetCore.Mvc.ApplicationParts
         /// <inheritdoc />
         public IEnumerable<string> GetReferencePaths()
         {
+            if (Assembly.IsDynamic)
+            {
+                // Skip loading process for dynamic assemblies. This prevents DependencyContextLoader from reading the
+                // .deps.json file from either manifest resources or the assembly location, which will fail.
+                return Enumerable.Empty<string>();
+            }
+
             var dependencyContext = DependencyContext.Load(Assembly);
             if (dependencyContext != null)
             {
diff --git a/src/Microsoft.AspNetCore.Mvc.Razor/Compilation/ViewsFeatureProvider.cs b/src/Microsoft.AspNetCore.Mvc.Razor/Compilation/ViewsFeatureProvider.cs
index b55052589e..407b7c8e12 100644
--- a/src/Microsoft.AspNetCore.Mvc.Razor/Compilation/ViewsFeatureProvider.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Razor/Compilation/ViewsFeatureProvider.cs
@@ -58,7 +58,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
         protected virtual Type GetViewInfoContainerType(AssemblyPart assemblyPart)
         {
 #if NETSTANDARD1_6
-            if (assemblyPart.Assembly.Location != null)
+            if (!assemblyPart.Assembly.IsDynamic && assemblyPart.Assembly.Location != null)
             {
                 var precompiledAssemblyFileName = assemblyPart.Assembly.GetName().Name
                     + PrecompiledViewsAssemblySuffix
diff --git a/test/Microsoft.AspNetCore.Mvc.Core.Test/ApplicationParts/AssemblyPartTest.cs b/test/Microsoft.AspNetCore.Mvc.Core.Test/ApplicationParts/AssemblyPartTest.cs
index b25e2b3ffc..b922a9eff0 100644
--- a/test/Microsoft.AspNetCore.Mvc.Core.Test/ApplicationParts/AssemblyPartTest.cs
+++ b/test/Microsoft.AspNetCore.Mvc.Core.Test/ApplicationParts/AssemblyPartTest.cs
@@ -1,9 +1,11 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System;
 using System.IO;
 using System.Linq;
 using System.Reflection;
+using System.Reflection.Emit;
 using Xunit;
 
 namespace Microsoft.AspNetCore.Mvc.ApplicationParts
@@ -81,5 +83,22 @@ namespace Microsoft.AspNetCore.Mvc.ApplicationParts
             var actual = Assert.Single(references);
             Assert.Equal(assembly.Location, actual);
         }
+
+        [Fact]
+        public void GetReferencePaths_ReturnsEmptySequenceForDynamicAssembly()
+        {
+            // Arrange
+            var name = new AssemblyName($"DynamicAssembly-{Guid.NewGuid()}");
+            var assembly = AssemblyBuilder.DefineDynamicAssembly(name,
+                AssemblyBuilderAccess.RunAndCollect);
+
+            var part = new AssemblyPart(assembly);
+
+            // Act
+            var references = part.GetReferencePaths().ToList();
+
+            // Assert
+            Assert.Empty(references);
+        }
     }
 }
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Test/Compilation/ViewsFeatureProviderTest.cs b/test/Microsoft.AspNetCore.Mvc.Razor.Test/Compilation/ViewsFeatureProviderTest.cs
index 081ff63254..5a41914aac 100644
--- a/test/Microsoft.AspNetCore.Mvc.Razor.Test/Compilation/ViewsFeatureProviderTest.cs
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Test/Compilation/ViewsFeatureProviderTest.cs
@@ -5,6 +5,7 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Reflection;
+using System.Reflection.Emit;
 using Microsoft.AspNetCore.Mvc.ApplicationParts;
 using Xunit;
 
@@ -69,6 +70,26 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Compilation
                 });
         }
 
+        [Fact]
+        public void PopulateFeature_ReturnsEmptySequenceIfNoDynamicAssemblyPartHasViewAssembly()
+        {
+            // Arrange
+            var name = new AssemblyName($"DynamicAssembly-{Guid.NewGuid()}");
+            var assembly = AssemblyBuilder.DefineDynamicAssembly(name,
+                AssemblyBuilderAccess.RunAndCollect);
+
+            var applicationPartManager = new ApplicationPartManager();
+            applicationPartManager.ApplicationParts.Add(new AssemblyPart(assembly));
+            applicationPartManager.FeatureProviders.Add(new ViewsFeatureProvider());
+            var feature = new ViewsFeature();
+
+            // Act
+            applicationPartManager.PopulateFeature(feature);
+
+            // Assert
+            Assert.Empty(feature.Views);
+        }
+
         private class TestableViewsFeatureProvider : ViewsFeatureProvider
         {
             private readonly Dictionary<AssemblyPart, Type> _containerLookup;